A Peeping Stiles
by softywolf
Summary: He must have looked like a mess, standing in the doorway like some kind of Peeping Tom. No, he was a fucking Peeping Stiles. He knew his face was flushed red from the arousal coursing through his body and the heat flooding his nether regions. Sterek. Erica/Lydia


Stiles had only meant to close his eyes for a few minutes. Just long enough to rid his eyes of the burning tiredness that lingered after spending an entire day running through the woods with the pack. The sun had still been up, shining through the blinds, when he'd curled up on the couch. It was dark now, shadows lining the living room.

While he'd slept, someone had covered him up with the afghan that was usually folded over the back of the couch. Stiles pushed the soft material to the side and sat up, a yawn escaping from his lips. He scrubbed the short hair on his head with the palm of his hand as he stood and stretched, bones popping deliciously with the arch of his back.

It was in that moment that Stiles realized that it was far too quiet for a house meant to be full of werewolves. The night before the full moon. At – Stiles glanced at the clock hanging on the wall above the entertainment center – nine o'clock in the evening. And as far as he could tell, he was alone. _Not a big deal_, he thought as he folded the afghan back up and returned it to its rightful place. Even though he was slightly suspicious, he decided to stay the night which led him up the stairs.

Stiles stumbled slightly in the dark as he made his way down the hall. He should have flipped the light switch on when he'd passed because he didn't have amazing werewolf abilities like the rest of the pack. Too late now. He sighed as he passed Isaac's room, the door closed with a 'caution' sign hanging from a thumbnail. _Giant girl-hating baby._

Just as he crossed the threshold into the guest room, he heard a noise. It was coming through the crack of the slightly opened door of Erica's room and, seeing as he had assumed the pack was running like hyped up puppies in the woods, he cautiously approached. Now that he was closer, he could discern two voices, one of which belonged to Erica. The other was…yeah, that was definitely Lydia. He was preparing to push the door open to see what the two were up to when Erica _moaned._ It was loud and sent a shot of heat straight to his groin. What? He was a dude. He didn't have or need any excuse for the way his body reacted.

"You like that?" He heard Lydia ask, her voice rough in a way that told Stiles she was totally digging whatever was happening. Erica's only response was to moan again. And when Stiles heard a wet suckling noise, he had to see. He _had _to see what was going on between the two hottest girls he had ever encountered.

He gently pressed his fingertips to the smooth wood and opened the door further. The groan that escaped his lips would be impossible to cover but he didn't care. Not when he saw Erica sprawled topless across her sheets, blonde hair spread around her head like a halo, and Lydia hovering over her. Stiles watched in awe as Lydia swiped her pink tongue over the bud of Erica's nipple. The trail that Lydia's hand was drawing up Erica's side caught Stiles' eye and he couldn't look away as her slender fingers grasped the part of Erica's breast that her mouth wasn't covering. He was so caught up in the way Lydia moved against the other girl's body that he didn't see the smirk cross Erica's face as she looked over at him.

He must have looked like a mess, standing in the doorway like some kind of Peeping Tom. No, he was a fucking Peeping Stiles. He knew his face was flushed red from the arousal coursing through his body and the heat flooding his nether regions.

"I….uh, sorry?" He tried when he met Erica's eye. Even if he knew he should be ashamed of himself for not leaving as soon as he knew what was going on, he was finding it rather difficult to be anything other than totally fucking turned on. "I'll just be going now."

"Or you could stay," Lydia suggested and Stiles' heart stopped. There was no fucking way he wasn't dead. He was dead and in Heaven because Lydia was telling him it was okay to stay and watch the two of them get it on. And well, even if he was dead and gone and in Heaven, he wasn't one to look a gift horse in the mouth.

"I could," Stiles said slowly, more of a question than anything, and he shuffled into the dim room. Neither of them waited around to see what Stiles was going to do. Lydia went back to pinching Erica's nipple between the tips of her fingers, only laughing when the blonde girl huffed and arched her hips up to press against Lydia's thigh. Stiles practically dove onto the computer chair and righted his self before rolling it across the floor until he found the best viewing position. He got situated just in time to watch Lydia pop the button on Erica's jeans and lower her mouth to the zipper. And _oh my god_, Stiles had to be dead because Lydia was unzipping Erica's jeans with her fucking teeth.

Stiles knew his mouth was hanging open and yeah, he was probably drooling. But holy shit, this was actually, honest-to-god happening right in front of him and he didn't even feel bad about the fact that he was palming his hardness through his pants.

"Why don't you take it out, Stiles?" Erica said once Lydia had helped her out of her jeans, tangling her fingers in the strawberry blonde hair atop Lydia's head. Just like Stiles had pictured himself doing all those years ago. Unsurprisingly, this was so much better than that. "You look like you could use some air down there."

If Stiles was anything, it was definitely not obedient. He usually did the exact opposite of what he was told. But he wasn't even going to think about that. Not when there was an insanely attractive female telling him to take his penis out. He had his pants undone and around his knees faster than he ever imagined possible and was wrapping his hand around the base of his dick when Lydia lowered her head between Erica's thighs. He couldn't stop the moan that fell from his lips at the sight, nor did he want to try. Especially not when it was taking all he had not to jerk off as fast as he could.

"Can you see?" Erica asked, in a kind of breathless tone that made Stiles grip his dick tighter. He shook his head and watched as she lifted one of her legs. Stiles could see then the way Lydia's nose was pressed against the mound of dark hair and the movement of her tongue as it lapped at Erica's shiny, wet pussy.

He really couldn't stop himself now. There was no way he could see this through all the way to the end. No chance in hell. Not even if it were raining. In hell. This was going to end so quickly that Stiles was probably going to just kill himself when it was done. His hand was pumping up and down, squeezing the head with every upward movement. The groans erupting from his tongue mixed with the whimpers falling from Erica's full lips and it was like a sweet chorus of sexy times filling the room.

Erica gently pushed Lydia's head away just when Stiles thought it sounded like she was going to come. The abruptness of it made him slow his hand down but he didn't stop. He sucked his bottom lip between his teeth as he twisted his wrist slightly. He'd been watching the way his fist moved up and down his cock and when he looked back up he found Erica assisting Lydia in the removal of her clothing. Erica was pretty much the opposite of Lydia when it came to undressing someone. Where Lydia had gone slow and seductively, Erica practically ripped Lydia's shirt off and shoved her shorts down her thighs. She flipped them so that she was on top, straddling Lydia's slender hips with a leg on each side of her body.

"You're being awfully quiet, hun," Erica quipped, tossing her hair over her shoulder as she looked back at him. He watched in awe as her thin fingers grasped Lydia's breasts and gave them a light squeeze, making the red-haired girl moan softly. "For you, anyway."

"I just…um, I-I," Stiles stuttered as he jerked himself faster, twisting his hand at the end of every upward movement.

"You like this, huh? Think it's fucking hot, don't you?" She trailed her fingers down the pale expanse of Lydia's flat stomach and smirked at the vigorous nod if his head. "Of course you fucking do. Look at you."

"As much as I like it when you cuss like a sailor when you're turned on, if you don't shut the hell up and get on with the your face plus my vagina equation, I'm going to-" Lydia cut off with a loud moan as Erica flicked her tongue over her hard, pink nipple. She pinched the other between her fingers, rolling it subtly. Stiles groaned out an 'oh fuck' and pressed his teeth against bottom lip until he tasted blood. He panted loudly, lips falling open with the force of air from his throat.

While Erica pressed loud, sloppy kisses against Lydia's skin, slowly moving from her collarbone to her belly button, Stiles sunk down in the chair, splaying his thighs open. He sucked his fingers into his mouth, tongue laving at them until they were dripping with his spit when he pulled them away from his lips. The slippery length of his fingers slid easily into the warmth of his ass. He grunted at the uncomfortable sensation but that quickly turned into a happy moan as he pressed against his prostate with the tips of his fingers. With slow movements, he thrust his fingers into himself and drug them back out; once, twice, three times before he lifted his eyes to look at the couple on the bed.

Both girls were watching him eagerly, Erica rubbing herself against Lydia's thigh.

"Wow, Stiles," she crooned as she watched him fingering himself open. "Jesus fuck, that's hot."

Lydia voiced her agreement as she gripped Erica's hips and pulled her down and closer. "Seriously, Stiles, that is probably the hottest thing-" Erica grumbled at her. "Besides Erica, of course." Erica attacked Lydia's mouth with her own, rocking her hips a few more times. She relocated her lips to lave at Lydia's neck, hand reaching down between them to slip fingers into Lydia's wetness. The sound that came from Lydia made Stiles' rhythm falter as he bit back a yelp.

He was so close. So fucking close. He had to stop. But he could only pump his dick faster, shoving his fingers in and out in time with Erica's fingers in Lydia. Oh god, he was about to –

"What the fuck?"

Stiles stopped touching himself immediately, fingers sliding out with a squelching noise that made him wince. He looked wide eyed at Derek who was standing in the doorway with an unreadable expression on his face. Erica continued to fuck into Lydia with her fingers but she pulled her mouth away to tell Derek to fuck off.

"Don't you know how to knock?" She sneered before returning her attention to the small girl below her.

"It's not what it looks like," Stiles cried, ignoring the way his erection bobbed between his legs. Or tried to anyways. "Oh god, this is not happening." He covered his face with his hands, heart pounding. He didn't look up when Erica said Derek's name in an angry tone. His plan consisted solely of cowering in the chair until the Earth opened up and swallowed him whole. That is, until he felt a hand on his bare thigh. A big, warm hand.

Stiles cautiously lowered his hand and found Derek kneeling in front of him. The noise that he made when Derek wrapped his thick fingers around his cock was a mixture between a shocked "what?" and a confused but very happy moan. "What are you doing?" He whispered, unable to take his eyes away from the stark contrast between Derek's tan fist and his own pale skin.

"Shut up, Stiles," Lydia demanded.

Derek lowered his mouth around Stiles, all warmth and wet and _oh my god_. Erica and Lydia had rearranged themselves so that their lower parts were aligned with one another. The wet sound of the two of them grinding together combined with Derek's _god fucking damn_ mouth was too much. Before he even knew what was happening, Stiles was emptying himself down Derek's throat, crying out with the force of his orgasm.

Derek pulled off with a pop, his lips swollen and wet. "Christ," he groaned as Stiles looked down at him through hooded lids. He popped the button on his jeans and tugged his heavy cock out. He wasted no time in grasping it at the base and moving his fist up and down and – holy shit, "Fuck!", he was using Stiles' come as lube, slicking his length up with it.

Stiles stood up and removed the rest of his clothing before he pushed Derek so he was lying flat on the floor. He straddled Derek's lap and pressed his chest against the larger man's.

"Stiles, what are you doing?" Derek asked, eyes dark and voice trembling. Stiles silenced any further questions or comments from Derek by capturing the older man's lips with his own. The kiss was slow and wet. When they parted, Derek was grasping Stiles' hips, thumbs pressing into pale flesh. The kiss had apparently given him the answer to his question. "You don't have to do this."

"Shut up, Derek," Stiles growled as he eased himself down Derek's length until he was fully seated in Derek's lap with a hard cock pressing against his prostate. "Oh fuck."

"Hey, Stiles?" Stiles grunted in acknowledgement so Erica kept talking. "You know how we were saying that thing you were doing before was hot? Yeah, this is way fucking hotter."

"Shut up, Erica," Derek growled as he lifted Stiles a little and began thrusting up into the warm heat surrounding his erection. He panted, head falling back as Stiles began to meet each of his thrusts with a downward twist of his hips. When he looked up at the pale, thin boy, he found that Stiles was biting his lip as he watched Lydia and Erica with wide eyes. Derek tilted his head until he could see too. They were both leaning back on their elbows, heads thrown back as they moaned loudly and pressed their slick pussies together over and over. "Jesus, this is so wrong."

"Nononono," Stiles mumbled fingers fumbling to grasp at Derek's shoulders. With something to hold onto, he began to ride Derek in earnest, picking a fast past that drove Derek absolutely fucking insane. "This is good. This is awesome."

"Stiles!" Derek cried as Stiles slammed down on him, the warm walls of his ass clenching around Derek's cock. Stiles made the same movement, pulling a loud cry from Derek again. One more downward thrust and Stiles was coming thick ropes across Derek's abdomen, mewling loudly as he continued to ride Derek. "Just like that, baby. Yesyesyes."

Derek came at the same time as Erica and Lydia, their shouts a symphony of pleasure ringing through the room. When he came down from his post coital high, Derek rearranged Stiles so that he was cradling him bridal style in his arms before lifting them both off of the ground. He glanced at the two girls snuggling with one another in the bed as he left the room.

Once in his own bedroom, Derek cleaned Stiles and himself off before tucking them both into bed, arms wrapped around Stiles' slender waist.

The next morning, when the pack gathered for breakfast, the four of them shared wicked glances but didn't breathe a word of what they'd done.


End file.
